BRITISH AVONIAN CONODONT FAUNAS 141 
Lonchodina furnishi Rexroad 
Plate 24, figs. 20a—23c 
1957 ?Lonchodina subsymmetrica Ulrich & Bassler ; Bischoff: Pl. 1, figs. 19, 21, 22. 
1958 Lonchodina furnish Rexroad : 22, Pl. 4, figs. 11-13. 
1961 Lonchodina furnish Rexroad ; Higgins: PI. 11, fig. 3. 
non 1962 Lonchodina furnish ? Rexroad ; Higgins: Pl. 1, fig. 4. 
1963 Lonchodina furnisht Rexroad ; Bouckaert & Higgins : 17, fig. 3. 
Lonchodina furnishi Rexroad ; Collinson & Druce (in press). 
MATERIAL. 5 Specimens : figured, X 225, X 226, X 228, X 227. 
Rance. North Crop 3D 8-3D 19. 
DESCRIPTION. The distinctive feature of this species is the more or less sym- 
metrical development of the cavity below the apical denticle on both sides of the bar, 
rather than being restricted to only one side of it. The anterior bar is stout and deep 
increasing slightly in depth towards the anterior end. It bears about 5 stout 
denticles which are basally confluent but discrete for two thirds of their length. 
They tend to be sub-triangular in profile and to be sharply pointed, with sharp 
anterior and posterior edges and gently to strongly convex lateral faces. The 
curvature on the outer faces tends to be stronger than that on the inner, the denticles 
on the median third of the bar tending to be the largest. The anterior denticle is 
small and relatively inconspicuous. The apical denticle is about twice the length of 
the largest denticle of the anterior bar ; it is strongly posteriorly inclined rather than 
recurved, its edges being straight. It lies in approximately the same horizontal plane 
as the distal end of the anterior bar. Its inner lateral face is strongly convex at the 
base, becoming feebly convex in its upper surface ; its outer lateral face is rather 
more strongly convex. Throughout its length it is sharply pointed and is also 
directed inwardly as well as posteriorly. The outer lateral face of the anterior bar is 
feebly ridged longitudinally along its upper surface, about one third of its depth below 
the junction with the oral denticles ; below this point it slopes gently inwards and 
has a flat feebly concave surface. The bar itself is curved in a vertical plane and is 
also slightly deflected inwardly. 
Bar Apical denticle 
denticles ee, 
Posterior Anteclor 
Posterior Anterior bar 
bar 
Aboral margin Inner lateral face 
Flared basal 
cavity 
Fig. 28. Lonchodina sp. showing morphological terms used in the text. 
